eMedicine Specialties > Urology > Stones

Bladder Stones

Author: Joseph Basler, MD, PhD, Chief, Section of Urology, Audie Murphy Veterans Affairs Hospital; Professor, Department of Urology, University of Texas Health Science Center at San Antonio
Coauthor(s): Aldo Ghobriel, MD, Staff Physician, Department of Surgery, Division of Urology, University of Texas Health Sciences Center at San Antonio; Jennifer J Lucas, MD, Staff Physician, Department of Urology, University of Texas Health Science Center at San Antonio
Contributor Information and Disclosures

Updated: Aug 10, 2007

Introduction

Bladder calculi are an uncommon cause of illness in most Western countries, but they result in specific symptoms and are a significant source of discomfort. This article discusses the diagnosis and current management techniques for vesical calculus disease. For excellent patient education resources, visit eMedicine's Kidneys and Urinary System Center and Procedures Center. Also, see eMedicine's patient education articles Cystoscopy, Intravenous Pyelogram, and Blood in the Urine.

History of the Procedure

Bladder stones have been treated both medically and surgically for many centuries. The oldest bladder stone discovered dates back to 4800 BC and was found by archeologists in Egypt around the turn of the 20th century. The first literary references to bladder stones date back to a time as early as, or earlier than, the time of Hippocrates. More than 23 centuries ago, Hippocrates warned that, "To cut through the bladder is lethal," and part of the Hippocratic oath includes, "I will not cut for stone, even for the patients in whom the disease is manifest; I will leave this operation to be performed by practitioners." His admonition to young physicians was to leave this highly risky and complicated procedure to the purveyors (ie, the lithotomists) of what could only be described as an art.

Famous historical figures who developed vesical calculi include King Leopold I of Belgium, Napoleon Bonaparte, Emperor Napoleon III, Peter the Great, Louis XIV, George IV, Oliver Cromwell, Benjamin Franklin, the philosopher Bacon, the scientist Newton, the physicians Harvey and Boerhaave, and the anatomist Scarpa.

Operations to remove bladder stones via the perineum were performed by Hindus, Greeks, Romans, and Arabs. Ammonius (200 BC), Celsus (first century), and the Hindu surgeon Susruta were among the first to write about perineal lithotomy to treat bladder calculi. They wrote excellent and sometimes detailed descriptions of the surgery, including preoperative and postoperative care and management. In the 1500s, Pierre Franco introduced suprapubic lithotomy. Frère Jacques Beaulieu developed the lateral approach to perineal vesicolithotomy in the late 1600s. An itinerant lithotomist with little anatomic understanding but impeccable character, Beaulieu performed the often lethal procedure in France through the early 1700s. He is remembered by the urologic community as the subject of an old French nursery rhyme, although some have suggested that it was really written as a satirical mockery of the Jacobinic monks whose order was popular in France at the time.

In an attempt to avoid incisions, another form of surgical treatment, transurethral lithotrity, became more common in the early 1800s. This technological advancement was made with the introduction of the fenestrated lithotrite, which allowed stones to be grasped and crushed so their fragments could be evacuated from the bladder via glass or metal suction bottles. Sir Philip Crampton was the first to introduce this concept in Dublin (circa 1834). However, litholapaxy was not firmly established until Henry J. Bigelow, the famous professor of surgery at Harvard, performed (1876) and popularized (1878) the procedure. The mechanical crushing of stones remained popular through the 1960s and 1970s, although it was fraught with complications when performed by inexperienced urologists.

In the 1950s, endoscopic electrohydraulic lithotripsy (EHL) was first performed in the Soviet Union. Over the next 4 decades, multiple other modalities have been developed and allow safe transurethral or percutaneous stone ablation.

Problem

Vesical calculi refer to the presence of stones or calcified materials in the bladder (or bladder substitute that functions as a urinary reservoir). These stones are usually associated with urinary stasis, but they can form in healthy individuals without evidence of anatomic defects, strictures, infections, or foreign bodies. The presence of upper urinary tract calculi is not necessarily a predisposition to the formation of bladder stones.

Frequency

The incidence of primary bladder calculi in the United States and Western Europe has been steadily and significantly declining since the 19th century because of improved diet, nutrition, and infection control. In these countries, vesical calculi affect adults, with a steadily declining frequency in children. In the Western hemisphere, vesical calculi primarily affect men who are usually older than 50 years and have associated bladder outlet obstruction. However, bladder calculi remain common in countries and areas such as Thailand, Burma, Indonesia, the Middle East, North Africa, and, in general, in developing and less-developed countries. In these populations, it remains a disease that affects children, among whom the disease is far more common in boys than in girls.

In 1977, Van Reen published a symposium on idiopathic urinary bladder stone disease.1 Unfortunately, no definitive worldwide data accurately reflect the frequency of bladder calculi. This is mostly because of poor hospital records in developing regions of the world. Despite several studies in countries with a high incidence of the disease, the reporting is not completely uniform.

Etiology

Bladder outlet obstruction remains the most common cause of bladder calculi in adults. The elevation of the bladder neck and high postvoid residual cause urinary stasis, which, despite gravitational forces, cannot overcome the intravesical prostate and prostatic urethral pressure. Crystals are formed in this static urine; therefore, larger calculi develop.

In addition, patients who have static urine and develop urinary infections are more likely to form bladder calculi. In a study of patients with spinal cord injuries (newly acquired neurogenic bladders) who were monitored for more than 8 years, 36% developed bladder calculi. Newer reports indicate that, because of better care of patients with injured spinal cords, this rate has dropped to less than 10%. Bladder inflammation secondary to external beam radiation or schistosomiasis can also predispose patients to vesical calculi.

Another etiologic factor of bladder stones is foreign bodies in the bladder that act as a nidus for stone formation. These are subclassified into iatrogenic and noniatrogenic bodies. The first group includes suture material, shattered Foley catheter balloons, eggshell calcifications that form on a catheter balloon, staples, ureteral stents, migrating contraceptive devices, and prostatic urethral stents. Noniatrogenic causes include objects placed into the bladder by the patients for recreational and various other reasons.

Metabolic abnormalities are not a significant cause of stone formation in patients with urinary diversions. In this group of patients, the stones are primarily composed of calcium and struvite.

In general, if an otherwise healthy person in the United States or Europe is found to have a bladder stone, a complete urological evaluation must be undertaken to find a cause for urinary stasis. Examples include benign prostatic hypertrophy, urethral stricture, neurogenic bladder, and bladder neck contracture. In females, examples include an incontinence repair that is too tight, cystoceles, and bladder diverticula.

Pathophysiology

In general, most vesical calculi are formed within the bladder, but some may initially have formed within the kidneys and subsequently passed into the bladder, where additional deposition of crystals may cause the stone to grow. However, most renal stones that are small enough to pass through the ureters are also small enough to pass through the urethra. In older men in whom stones are composed of uric acid, the stone most likely formed in the bladder. Stones composed of calcium oxalate are usually initially formed in the kidney.

The most common type of stone in adults is composed of uric acid (>50%). In the pediatric population, most bladder calculi are found in endemic areas and are composed mainly of ammonium acid urate, calcium oxalate, or an impure mixture of ammonium acid urate and calcium oxalate with calcium phosphate. The common link between these endemic areas relates to feeding infants human breast milk and polished rice. These foods are low in phosphorus, ultimately leading to high ammonia excretion. These children also usually have a high intake of oxalate-rich vegetables (increased crystalluria) and animal protein (low dietary citrate). Bladder stones in patients with spinal cord injuries are often composed of struvite or calcium phosphate.

Vesical calculi may be single or multiple, especially in the presence of bladder diverticula. Vesical calculi can be small or large enough to occupy the entire bladder. Their physical features range from being soft to extremely hard and from having smooth-faceted surfaces to jagged spiculated surfaces (termed "jack" stones based on their resemblance to the metal objects in the children's game Jacks [see Image 5]). In general, most vesical calculi are mobile within the bladder, although some stones are fixed when they form on a suture, on the intravesical portion of a papillary tumor or polyp, or on retained stents.

In regions where vesical lithiasis is endemic among children, a pattern appears to exist.

  • Pediatric stones are more common among boys younger than 11 years.
  • Pediatric stones are not usually associated with renal calculi.
  • Pediatric stones are relatively less likely to reoccur after treatment (when compared with upper tract calculi).
  • Pediatric stones are common among people from low socioeconomic backgrounds.

Presentation

Patients with vesical calculi may be completely asymptomatic. More often, however, patients report suprapubic pain, dysuria, intermittency, terminal gross hematuria, frequency, hesitancy, and nocturia. Another common symptom is sudden termination of voiding with some degree of associated pain, which may be referred to the tip of the penis, scrotum, perineum, back, or hip. The discomfort may be dull or sharp and is often aggravated by sudden movements and exercise. Assuming a supine, prone, or head-down position may alleviate the pain initiated by the stone impacting the bladder neck. Parents of children with vesical calculi may notice priapism and occasional enuresis.

Common physical examination findings include suprapubic fullness and, occasionally, a palpable distended bladder if the patient is in acute urinary retention. Associated findings include cystoceles in women, high postvoid residuals, and neurological deficits in people with a neurogenic bladder.

Signs of vesical calculi include microscopic or gross hematuria, pyuria, bacteriuria, crystalluria, and urine cultures that demonstrate urea-splitting organisms.

Historically, bladder calculi were diagnosed based on transurethral passage of van Buren sounds. The contact of the van Buren sounds with the stones causes transmission of a clicking noise or vibration, which confirms the presence of the stone. This maneuver is rarely used today. Currently, abdominopelvic plain radiography is used to easily identify radiopaque stones. However, adult calculi, which are composed predominantly of uric acid, may be radiolucent and, unless coated with calcium, are more difficult to visualize on plain radiographs. Cystoscopy, noncontrast CT scan, and ultrasonography are common methods used to confirm the presence of bladder calculi.

Indications

Indications for surgery to remove bladder calculi include failure of medical management, recurrent infections, acute urinary retention, suprapubic pain, and significant gross hematuria. In addition to treating the stone, also investigate and correct the etiology of the underlying cause of stone formation (eg, bladder outlet obstruction, infections, foreign body, diet). Recent literature describes treatment of bladder calculi without relieving outlet obstruction, but the follow-up period was not long enough to warrant this as general practice.

Relevant Anatomy

In men, the main anatomical problem that leads to vesical obstruction is prostatic enlargement. The prostate forms a ringlike growth around the vesical neck and, when hypertrophic, can significantly impede the flow of urine. Stasis due to this blockage is responsible for the deposition of layer upon layer of new stone material.

In women, voiding dysfunction and urinary stasis can occur but are less commonly associated with calculi. Any foreign body that cannot escape the bladder is calcified and eventually forms a stone.

Contraindications

In general, most vesical calculi procedures are performed via endoscopy. However, when the stone is too large or hard or when the patient's urethra is too small (eg, in children), the open or percutaneous suprapubic surgical approach is preferable.

Relative contraindications to EHL include small-capacity bladder, possibly pregnancy, and the presence of cardiac-pacing or defibrillation devices.

Contraindications to percutaneous lithotripsy include prior lower abdominal surgery, prior pelvic surgery, and small-capacity noncompliant bladders.

Pregnancy is a relative contraindication to some forms of lithotripsy (eg, electrohydraulic shock-wave lithotripsy [ESWL]), EHL, mechanical lithotrite), but the benefits of eliminating a source of infection, retention, or pain with other modalities (eg, holmium laser, lithoclast) may outweigh the risk of intervention.

Otherwise, the usual contraindications to any type of surgery apply here as well.

More on Bladder Stones

Overview: Bladder Stones
Workup: Bladder Stones
Treatment: Bladder Stones
Follow-up: Bladder Stones
Multimedia: Bladder Stones
References
Further Reading

References

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Further Reading

For additional information on bladder stones, see Medscape's Stone Disease Resource Center.

Keywords

vesical calculi, bladder calculi, vesical stones, bladder stones, vesical calculus disease, perineal lithotomy, perineal vesicolithotomy, transurethral lithotrity, endoscopic electrohydraulic lithotripsy, EHL, urinary stasis, bladder outlet obstruction, urinary bladder stone disease, benign prostatic hypertrophy, urethral stricture, neurogenic bladder, bladder neck contracture, incontinence repair, cystoceles, bladder diverticula, uric acid, calcium oxalate, electrohydraulic shock-wave lithotripsy, ESWL, mechanical lithotrite, transurethral cystolitholapaxy, percutaneous suprapubic cystolitholapaxy, open suprapubic cystostomy

Contributor Information and Disclosures

Author

Joseph Basler, MD, PhD, Chief, Section of Urology, Audie Murphy Veterans Affairs Hospital; Professor, Department of Urology, University of Texas Health Science Center at San Antonio
Joseph Basler, MD, PhD is a member of the following medical societies: American Urological Association, Society for Basic Urologic Research, Society of University Urologists, Society of Urologic Oncology, and Southwestern Oncology Group
Disclosure: Nothing to disclose.

Coauthor(s)

Aldo Ghobriel, MD, Staff Physician, Department of Surgery, Division of Urology, University of Texas Health Sciences Center at San Antonio
Aldo Ghobriel, MD is a member of the following medical societies: American Medical Association and American Urological Association
Disclosure: Nothing to disclose.

Jennifer J Lucas, MD, Staff Physician, Department of Urology, University of Texas Health Science Center at San Antonio
Jennifer J Lucas, MD is a member of the following medical societies: American Urological Association and Society of Women in Urology
Disclosure: Nothing to disclose.

Medical Editor

Leonard Gabriel Gomella, MD, FACS, The Bernard W Godwin Professor of Prostate Cancer Chairman, Department of Urology, Associate Director of Clinical Affairs, Kimmel Cancer Center, Thomas Jefferson University
Leonard Gabriel Gomella, MD, FACS is a member of the following medical societies: American Association for Cancer Research, American College of Surgeons, American Medical Association, American Society for Laser Medicine and Surgery, American Urological Association, Sigma Xi, Society for Basic Urologic Research, Society of University Urologists, and Society of Urologic Oncology
Disclosure: GSK Consulting fee Consulting; Astra Zeneca Honoraria Speaking and teaching

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Martin I Resnick, MD †, Former Lester Persky Professor and Chair, Department of Urology, Former Professor, Department of Oncology, Case Western Reserve University School of Medicine
Martin I Resnick, MD † is a member of the following medical societies: American College of Surgeons, American Federation for Medical Research, American Institute of Ultrasound in Medicine, American Medical Association, American Society for Bone and Mineral Research, American Society for Reproductive Medicine, American Society of Andrology, American Surgical Association, American Urological Association, Association for Academic Surgery, Endocrine Society, National Kidney Foundation, Ohio Urological Society, and Pan American Medical Association
Disclosure: Nothing to disclose.

CME Editor

J Stuart Wolf, Jr, MD, FACS, David A Bloom Professor of Urology, Director, Division of Minimally Invasive Urology, Department of Urology, University of Michigan Medical Center
J Stuart Wolf, Jr, MD, FACS is a member of the following medical societies: American College of Surgeons, American Medical Association, American Urological Association, Catholic Medical Association, Endourological Society, Society for Urology and Engineering, Society of Laparoendoscopic Surgeons, and Society of University Urologists
Disclosure: Terumo Corporation Consulting fee Consulting; Omeros Corporation Consulting fee Consulting

Chief Editor

Stephen W Leslie, MD, FACS, Founder and Medical Director, Lorain Kidney Stone Research Center; Clinical Assistant Professor, Department of Urology, University of Toledo
Stephen W Leslie, MD, FACS is a member of the following medical societies: American College of Surgeons, American Urological Association, National Kidney Foundation, and Ohio State Medical Association
Disclosure: Nothing to disclose.

 
 
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